• 센서학회지
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• 제24권2호
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• pp.83-87
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• 2015

In this paper, we fabricated a low-cost glucose sensor with a simpler structure and fabrication process than the existing glucose sensor. The currently used glucose sensor has a three-layer structure with upper, middle, and bottom plates; here, we fabricated a single-layer glucose sensor using only a printing and dispensing process. We successfully fabricated the glucose sensor using a simple method involving the formation of an electrode and insulator layer through a 2- or 3-step printing process on plastic or paper film, followed by the dispensing of glucose oxidase solution on the electrode. Cyclic voltammetry (CV) and cyclic amperometry (CA) measurements were used to evaluate the characteristics of the fabricated single-layer glucose sensor. Also, its sensitivity was analyzed through glucose-controlled blood measurements. Hence, a low-cost single-layer glucose sensor was fabricated with evaluation of its characteristics demonstrating that it has useful application in medicine.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 센서 박막재료
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• pp.6-10
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• 2001

We synthesized polypyrrole (PPy) nanotubules by oxidative polymerization of the pyrrole monomer on the pore of a polycarbonate membrane. The electrochemical behavior was investigated using cyclic voltammetry and AC impedance. The redox potential was about -0.5 V vs. Ag/AgCl reference electrode, while the potential was about 0 V for electro-synthesized PPy film. It is considered as the backbone grows according to the pore wall. Therefore, it is possible to be arranged regularly. That leads to improvement in the electron hopping. The AC impedance plot gave a hint of betterment of mass transport. PPy nanotubules have improved in mass transport, or diffusion. That is because the diffusion occurs through a thin pore wall of PPy nanotubules. The kinetic parameter of PPy nanotubules enzyme electrode with glucose solution was evaluated. The formal Michaelis constant and maximum current calculated by computer were about 23.8 mmol $dm^{-3}$ and $440\;{\mu}A$ respectively. Obviously, an affinity for the substrate and current response of the PPy nanotubules enzyme electrode are rather good, comparing with that of PPy film. What is more, the enzyme electrode is sensitive to blood sugar of a diabetic serum despite an obstruction of ascorbic acid, oxygen, some protein and/or hormone.

• BMB Reports
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• 제34권5호
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• pp.463-471
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• 2001

The bark of Ulmus darvidiana var. japonica Nakai (UDN) has been used for a long time to cure inflammation in oriental medicine. In the present study, two types of extracts, Ulmus water-eluted fraction (UWF) and Ulmus ethanol-eluted fraction (UEF), were prepared from the UDN stem bark, and employed to test the extracts to see if they had anti-oxidative properties against hydroxyl radicals that could alter immune reactivity in mouse immune cells. Deoxyribose assay, DNA nicking assay, and glucose/glucose oxidase assay showed that both fractions had scavenging activity against oxygen free radicals at 50 mg/ml. In addition, hydroxyl radical-mediated apoptosis in mouse thymocytes was not protected by UEF treatment, but the apoptosis was protected by UWF at the same concentration. DNA synthesis and cytokine production that were induced in splenocytes by mitogens (Concanavalin A and lipopolysaccharide) were reduced by the addition of both fractions. These results indicate that both extracts that were prepared from the UDN stem bark have anti-oxidative activities, anti-apoptotic effects, and inhibitory effects on DNA synthesis and cytokine production in mouse immune cell cultures.

• 대한화학회지
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• 제23권3호
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• pp.165-174
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• 1979

토양중에서 분리한 Penicillium속이 생산하는 글루코오스 옥시타아제를 친화성 크로마토그래피에 의해 정제하고, 이 효소의 특성을 알아보았다. D-Gluconyl-${\omega}$-aminohexyl Sepharose컬럼을 사용하여 친화성 크로마토그래피를 행한 결과 14.6배 정제되었고 수율은 79%였으나 카탈라아제가 소량 함유되어 있어서 Sepharose 6B 겔 여과를 행하여 이를 제거하였다. 이 결과 27.2배 정제되고 수율이 74.1%인 정제효소를 얻었으며 7% polyacrylamide 겔 전기영동 결과 단일대를 보여주었고 비활성도는 단백질 mg당 90.83U였다. 정제된 효소의 흡광스펙트럼과 기질에 대한 특이성을 조사하였으며 최적 pH는 5.6∼6.0, 최적온도는 $40^{\circ}C$, D-글루코오스에 대한 $K_m$값은 $8.5{\times}10^{-3}M$, 활성화에너지는 3.43 kcal/mole이었다.

• Journal of Animal Science and Technology
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• 제63권4호
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• pp.778-789
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• 2021

The objective of this study is to investigate the effect of dietary glucose oxidase (GOx) supplementation on the reproductive performance, litter performance, total tract digestibility, and blood profile of lactating sows fed corn- wheat-based diet. A total of twenty multiparous sows (Landrace × Yorkshire) were allocated into one of four treatments with five replicates per treatment. The dietary treatments were as follows: CON (Basal diet), GO1 (basal diet + 200 U GOx/kg), GO2 (basal diet + 300 U GOx/kg), GO3 (basal diet + 400 U Gox/kg). Dietary GOx supplementation did not affect lactating sow's reproduction performance as well as body weight, backfat thickness, and body condition score during pre and post farrowing, and at weaning (p > 0.05). However, after farrowing to weaning period lactating sow's fed GOx supplement has linearly (p = 0.0196) decreased the bodyweight loss. While, there were no effects (p > 0.05) observed on sows backfat thickness loss, average daily feed intake, and estrus interval among treatment groups. Dietary supplementation of GOx has linearly improved the body weight gain (p = 0.049) and average daily gain (p = 0.040) of suckling piglets. The total tract digestibility of dry matter and nitrogen was linearly increased with the graded level of GOx supplement. Also, a linear effect was observed on the glucose and superoxide dismutase of blood profile with the dietary inclusion of GOx. In summary, our finding indicates that the dietary inclusion of GOx supplement with corn- wheat-based diet had a beneficial effect on the nutrient digestibility and blood profile of lactating sows and improved the growth performance of suckling piglets.

• 반도체디스플레이기술학회지
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• 제19권4호
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• pp.116-120
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• 2020

In this paper, we developed an electrochemical glucose sensor strip using a paper substrate. The paper glucose sensor strip is eco-friendly because it uses paper as a substrate, and it has the advantage that it can be manufactured only with four printing, drying and cutting processes. The paper glucose sensor is significantly simplified by the production process than the conventional glucose sensors because the production of only four printing on the paper substrate. In this paper, eco-friendly tracing paper was used to develop a paper glucose sensor strip, and screen-printing technology was used to form a carbon/silver electrode, insulating layer and glucose oxidase(GOD) layer. The developed paper glucose sensor strip has a flat structure with a size of 30 × 4.6 ㎟, and blood injection is a type of direct contact with the exposed enzyme layer above the strip. In this paper, the performance of paper glucose sensor strips was evaluated by analyzing the cyclic voltammetry(CV) and chronoamperometry(CA) characteristics.

• 미생물학회지
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• 제40권3호
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• pp.248-253
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• 2004

2000년 9월부터 2002년 12월 사이에 바이칼호에서 분리된 빈영양성 세균 168균주와 저온성 세균 132균주를 대상으로 BIOLOG Microplate를 이용하여 탄소원의 이용특성을 조사하였다. 본 연구에 사용된 빈영양성 세균 중 oxidase 양성 (GN-NENT 그룹)의 86% (56균주)와 oxidase음성 (GN-ENT그룹)의 89% (92균주), 저온성 세균 중 oxidase 음성 (GN-ENT 그룹)의 82% (85균주)는 다앙한 탄소원 중에서 $\alpha$-D-glucose를 이용할 수 있었으며, 저온성 세균 중 oxidase 양성 (GN-NENT 그룹)의 93% (26 균주)는 bromosuccinic acid를 이용하였다. $\alpha$-D-lactose는 빈영양성 GN-ENT 그룹의 일부만이 이용하였으며 나머지 균주들은 전혀 이용하지 못하였다. BIOLOG Microplate를 이용하여 동정된 균들을 속별로 살펴보면, Pseudomonas속이 49균주로 가장 많았으며, 그 외에도 Salmonella 속, Serratia속, Buttiauxella 속, Pantoea 속, Yersinia 속, Brevundimonas 속, Hydrogenophaga 속, Photorhabdus 속, Sphingomonas 속, Xenorhabdus 속이 동정되었다.

• 센서학회지
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• 제27권3호
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• pp.156-159
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• 2018

We developed a glucose sensor using glucose dehydrogenase flavin adenine dinucleotide (GDH-FAD). The structure of the three-layer glucose sensor was simplified, in which a single-layer design was used to lower the unit cost, and GDH-FAD was used to increase the measurement reliability. GDH-FAD has less impact on the 20 interfering substances that affect blood glucose measurement, such as galactose and maltose compared to glucose oxidase (GOD), and is not affected by the oxygen saturation; therefore, it is possible to measure both arterial or venous blood and thus less susceptibility to hematocrit. In this study, we developed a single-layer glucose sensor strip with low hematocrit effect using the GDH-FAD enzyme, and measured and evaluated the performance.

• 전기화학회지
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• 제23권3호
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• pp.66-72
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• 2020

본 연구에서는 글루코스 검출을 위한 HRP (horseradish peroxidase)와 GOD (glucose oxidase)를 혼합한 형태의 다중 효소 반응 바이오센서 개발연구를 수행하였다. 바이오센서는 제작 시간 단축을 위하여 전기전착법을 이용하여 제작하였으며, 경제적인 센서 제작을 위하여 SPE (screen printed electrode)를 사용하였다. 다중 효소 바이오센서의 효과를 확인하기 위하여 단일 효소 바이오센서를 제작하여 비교 및 분석하였다. 센서의 특성을 평가하기 위해서 주사전자현미경(scanning electron microscopy, SEM), 순환전위법(cyclic voltammetry, CV), 전기화학적 임피던스 분광법(electrochemical impedance spectroscopy, EIS), 시간대전류법(chronoamperometry, CA), 흐름 주입분석법(flow injection analysis, FIA)를 수행하였다. SEM, CV, EIS의 분석결과로부터 효소가 전극 표면에 고정화가 잘 된 것을 확인하였고, CA로부터 제작된 다중 효소 바이오센서가 단일 효소 바이오센서에 비해 신호성능이 200% 향상된 것을 확인하였다. 이로부터 HRP와 GOD가 서로 촉매적으로 반응한다는 것을 설명할 수 있었다. 또한, FIA의 결과에서 동일한 농도의 글루코스 용액을 4회 나누어 주입하였을 때, 전류신호량이 일정함을 확인하였고, 농도에 따른 전류신호량을 분석하여 신호민감성, 재현성, 안정성 등이 우수함을 설명할 수 있었다.

• 한국미생물·생명공학회지
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• 제26권1호
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• pp.68-75
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• 1998

A. niger의 GOD(Glucose Oxidase) 대량생산과 효율적인 분비를 protein의 대량생산에 많이 사용되는 strain인 S. cerevisiae에서 시도하였다. S. cerevisiae의 ADH1과 GAL 10 promotor, 그리고 ${alpha}$-MF signal sequence와 A. oryzae의 ${alpha}$-amylase signal sequence 및 S. cerevisiae의 GAL7과 A. niger의 GOD terminator를 이용하여 4개의 expression vector를 합성한 후 S. cerevisiae 2805에 auxotroph 방법으로 형질변환시켰다. 변이체들을 배양하여 세포내와 세포외의 GOD활성도를 분석한 결과 GAL 10 promotor가 삽입된 pGAL변이체들이 ADH1 promotor가 삽입된 pADH 변이체들 보다 GOD 생산성이 높았다. GAL 10 promotor와 A. oryzae의 ${alpha}$-amylase signal sequence가 삽입된 pGALGO2에서 115시간 배양시 GOD의 생산이 가장 높았다($GOD_{total}$: 10.3 unit/mL, $GOD_{ex}$: 8.7 unit/mL). 이 수치는 같은 promotor인 GAL 10 promotor와 ${alpha}$-MF signal sequence가 삽입된 pGALGO1보다 3배정도 높다. 이 결과는 ADH 1 promotor를 사용하였을 경우에도 일치하였다. 또한 A. oryzae의 ${alpha}$-amylase signal sequence가 S. cerevisiae의 ${alpha}$-MF signal sequence보다 GOD를 더 효과적으로 분비시켰다. 상기 결과로 미루어 보면 signal sequence가 단백질의 분비 외에도 단백질 합성에도 많은 영향을 주는 것으로 추측된다. pGALGO1과 pGALGO2의 GOD분비효율은 각각 89%, 84%이었다. S. cerevisiae에서는 일반적으로 과당화가 일어나기 때문에 S. cerevisiae에서 합성된 재조합 GOD의 분자량은 250 kDa으로 A. niger의 GOD(170 kDa)보다 더 컸다.